Hemodialysis treatment apparatus and method for hemodialysis treatment

ABSTRACT

A hemodialysis treatment apparatus includes a circulating blood volume variation rate detecting device, a vital sign detecting device and a display. The circulating blood volume variation rate detecting device detects a circulating blood volume variation rate of a patient in a time-course of a hemodialysis treatment. The vital sign detecting device detects a vital sign value of the patient in the time-course of the hemodialysis treatment. The display has a screen and displays both the circulating blood volume variation rate and the vital sign value on the screen along a time scale. The hemodialysis treatment apparatus dialyzes and ultrafiltrates extracorporeally circulating blood of the patient to perform the hemodialysis treatment.

INCORPORATION BY REFERENCE

The present application claims priority under 35 U.S.C. §119 to JapanesePatent Application No. 2005-181721 filed on Jun. 22, 2005, the entirecontents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an apparatus for hemodialysistreatment, which performs hemodialysis and ultrafiltration byextracorporeally circulating blood of a patient.

2. Discussion of the Background

A conventional apparatus for hemodialysis treatment includes a bloodcircuit, a dialyzer, a blood pump and a dialysis device. The bloodcircuit circulates blood of a patient extracorporeally, and is connectedto the dialyzer. The dialysis device performs hemodialysis andultrafiltration by having dialysate flow into and out from the dialyzer.The blood circuit has an arterial blood circuit provided with anarterial needle at an end thereof, and a venous blood circuit providedwith a venous needle at an end thereof.

When the arterial needle and the venous needle are inserted to thepatient, and the blood pump is turned on, blood of the patient flowsthrough the arterial needle into the arterial blood circuit, thedialyzer and the venous blood circuit in sequence, and then flows backinto the body of the patient through the venous needle. The dialyzerincludes hollow fibers forming membranes for hemodialysis. The bloodflows inside of the hollow fibers. The dialysate, which has apredetermined concentration and is supplied from the dialysis device,flows outside the hollow fibers (i.e., between outside surfaces of thehollow fibers and an inside surface of a case of the dialyzer). Wasteproducts in the blood flowing in the inside of the hollow fiberspermeate into the dialysate through the membranes.

The blood flows back to the body of the patient after flowing throughthe venous blood circuit and after the waste products being removed fromthe blood. Also, the dialysis device is provided with an ultrafiltrationpump that removes water from the blood. The blood is also ultrafiltratedthrough the membranes during the hemodialysis treatment. A volume ofwater to be ultrafiltrated by the ultrafiltration pump (i.e., anultrafiltration rate) is adjusted by controlling a driving rate of theultrafiltration pump.

When an ultrafiltration volume (i.e., a volume of water to beultrafiltrated) is large, it is necessary to increase theultrafiltration rate. Consequently, the patient may show shock symptoms,such as a low blood pressure, depending on health conditions of thepatient. Accordingly, the conventional apparatus monitors a sign of theshock symptoms during the hemodialysis treatment by detecting ahematocrit value of the blood of the patient (i.e., a ratio of a volumeof red blood cells to a volume of whole blood), and by calculating acirculating blood volume variation rate (herein “ΔBV”) of the patientbased on the hematocrit value, so as to predict the sign of such shocksymptoms.

In this regard, although the ΔBV of the patient normally decreases dueto the ultrafiltration in a time-course of the hemodialysis treatment, asudden decrease in the ΔBV is considered to indicate the sign of theshock symptoms. Thus, it is possible to prevent an actual showing of theshock symptoms by performing a proper preventive treatment to thepatient (e.g., additionally supplying saline and suspending thehemodialysis treatment) at the time the sudden decrease in the ΔBVoccurs. The above described apparatus for hemodialysis treatment isdescribed in the Japanese Patent Application Publication No. 2004-97781.

However, sudden changes in the ΔBV may also occur due to external eventssuch as changes in the ultrafiltration rate and hemodialysis conditions,in body positions of the patient from lying down to sitting up on thebed, and in taking food and medications. In the above-describedconventional apparatus, it is difficult to compare the ΔBV with vitalsigns of the patient (e.g., bio-information of the patient during thehemodialysis treatment, such as a blood pressure and a pulse) thatindicate the occurrence of the external events. Therefore, it isdifficult to effectively relate the sudden changes in ΔBV to the sign ofthe shock symptoms.

In this regard, a conventional apparatus having a display is availableto independently display each of the ΔBV and the vital signs in arespective screen, one screen at a time on the display, thereby having amedical staff switch between multiple screens to monitor the ΔBV and thevital signs. Also, other conventional apparatuses are available, eachdedicated to detect and display either the vital signs or the ΔBV.Accordingly, a medical staff compares changes of the ΔBV and the vitalsigns displayed on multiple apparatuses to identify a cause of thesudden changes of the ΔBV when occurred. Consequently, when theabove-described apparatus or apparatuses are used, because a medicalstaff is required to watch multiple screens independently by switchingfrom one to another, or to shift the eyes between multiple apparatuses,the medical staff cannot efficiently and effectively monitor the ΔBV andthe vital signs, thereby making difficult to determine whether thesudden changes in the ΔBV indicate the sign of the shock symptoms.

SUMMARY OF THE INVENTION

According to one aspect of the present invention, a hemodialysistreatment apparatus includes a circulating blood volume variation ratedetecting device, a vital sign detecting device and a display. Thecirculating blood volume variation rate detecting device detects acirculating blood volume variation rate of a patient in a time-course ofa hemodialysis treatment. The vital sign detecting device detects avital sign value of the patient in the time-course of the hemodialysistreatment. The display has a screen and displays both the circulatingblood volume variation rate and the vital sign value on the screen alonga time scale. The hemodialysis treatment apparatus dialyzes andultrafiltrates extracorporeally circulating blood of the patient toperform the hemodialysis treatment.

Because the display displays both the circulating blood volume variationrate and the vital sign value on the same screen along the time scale,the circulating blood volume variation rate and the vital sign value areefficiently and effectively compared when the sudden changes in thecirculating blood volume variation rate occur. As a result, it isefficiently and effectively determined whether such sudden changes isthe sign of the shock symptoms.

According to another aspect of the present invention, a method forhemodialysis treatment includes dialyzing and ultrafiltratingextracorporeally circulating blood of a patient to perform ahemodialysis treatment. A circulating blood volume variation rate of thepatient is detected in a time-course of the hemodialysis treatment. Avital sign value of the patient is detected in the time-course of thehemodialysis treatment. Then, both the circulating blood volumevariation rate and the vital sign value are displayed on a screen of adisplay along at least one time scale.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete appreciation of the invention and many of the attendantadvantages thereof will be readily obtained as the same becomes betterunderstood by reference to the following detailed description whenconsidered in connection with the accompanying drawings, wherein:

FIG. 1 is a schematic diagram of a hemodialysis treatment apparatusaccording to an embodiment of the present invention;

FIG. 2 is a schematic diagram of a dialysis device in the hemodialysistreatment apparatus according to the embodiment of the presentinvention, showing an internal structure of the dialysis device;

FIG. 3 is an exterior perspective view of the dialysis device accordingto the embodiment of the present invention;

FIG. 4 is a block diagram of the dialysis device according to theembodiment of the present invention, showing an internal structure ofthe dialysis device;

FIG. 5 is a schematic diagram of a screen of a display provided at thedialysis device of the embodiment of the present invention;

FIG. 6 is a schematic diagram of a screen of a display provided at adialysis device of another embodiment of the present invention; and

FIG. 7 is a schematic diagram of a screen of a display provided at adialysis device of yet another embodiment of the present invention.

DESCRIPTION OF THE EMBODIMENTS

The embodiments will now be described with reference to the accompanyingdrawings, wherein like reference numerals designate corresponding oridentical elements throughout the various drawings.

A hemodialysis treatment apparatus according to the present invention isused to perform hemodialysis and ultrafiltration by extracorporeallycirculating blood of a patient. FIG. 1 is a schematic diagram of thehemodialysis treatment apparatus that includes a blood circuit 1, adialyzer 2 and a dialysis device 6. As shown in FIG. 1, the bloodcircuit 1 is provided with an arterial blood circuit 1 a and a venousblood circuit 1 b each made from flexible tubing, and circulates theblood of the patient. The dialyzer 2 is connected to the blood circuit 1between the arterial blood circuit 1 a and the venous blood circuit 1 band performs hemodialysis. The dialysis device 6 is connected to thedialyzer 2 to supply dialysate and to ultrafiltrate the blood.

The arterial blood circuit 1 a is provided at an end thereof with anarterial needle a, and also provided therealong with a blood pump 3 anda hematocrit sensor 5. The venous blood circuit 1 b is provided at anend thereof with a venous needle b, and also provided therealong with avenous drip chamber 4 to remove air bubbles.

The hematocrit sensor 5 has a photo emitter (e.g., a light emittingdiode) and a photo detector (e.g., a photo diode), and measures ahematocrit value indicating a concentration of the blood. Specifically,the hematocrit sensor 5 measures the hematocrit value by emitting alight with a predetermined wave-length to the blood from the photoemitter, and detecting either a transmitted or reflected light by thephoto detector. The hematocrit value indicates a ratio of a volume ofred blood cells to a volume of whole blood.

When the blood pump 3 is turned on while the arterial needle a and thevenous needle b are inserted to the patient, the blood of the patientflows through the arterial blood circuit 1 a into the dialyzer 2 thatdialyzes the blood. Subsequently, the blood returns to the body of thepatient through the venous blood circuit 1 b after bubbles are removedby the venous drip chamber 4. Thus, the blood is dialyzed by thedialyzer 2 during extracorporeal circulation through the blood circuit1.

The dialyzer 2 is provided with a blood inlet port 2 a, a blood outletport 2 b, a dialysate inlet port 2 c and a dialysate outlet port 2 d.The blood inlet port 2 a and the blood outlet port 2 b are eachconnected to ends of the arterial blood circuit 1 a and the venous bloodcircuit 1 b, respectively. Additionally, a dialysate inlet line L1 and adialysate outlet line L2 are each extended from the dialysis device 6,and are each connected to the dialysate inlet port 2 c and the dialysateoutlet port 2 d, respectively.

The dialyzer 2 includes a plurality of hollow fibers. The blood flowsinside the hollow fibers, and the dialysate flows between outsidesurfaces of the hollow fibers and an inside surface of a case of thedialyzer 2. The hollow fibers are provided with a plurality ofmicropores on the inside and outside surfaces of the hollow fibers. Thisforms permeable membranes which allow waste products in the blood topermeate into the dialysate.

FIG. 2 is a schematic diagram showing a mechanical structure of thedialysis device 6 in the hemodialysis treatment apparatus. As shown inFIG. 2, the dialysis device 6 includes a duplex pump P, a bypass line L3and an ultrafiltration pump 8. The duplex pump P is connected to boththe dialysate inlet line L1 and the dialysate outlet line L2, bridgingthe two lines L1 and L2. The bypass line L3 is connected to thedialysate inlet line L2 bypassing the duplex pump P, and is alsoconnected to the ultrafiltration pump 8. The dialysate inlet line L1 isconnected at one end thereof to the dialysate inlet port 2 c of thedialyzer 2, and at another end thereof to a dialysate supplying device 7that adjusts the dialysate to a predetermined concentration.

The dialysate outlet line L2 is connected at one end thereof to thedialysate outlet port 2 d of the dialyzer 2, and at another end thereofto a fluid disposal device (not shown). The dialysate supplied from thedialysate supplying device 7 flows through the dialysate inlet line L1into the dialyzer 2, then, flows through the dialysate outlet line L2and the bypass line L3 into the fluid disposal device.

The ultrafiltration pump 8 ultrafiltrates the blood to remove water fromthe blood flowing in the dialyzer 2. When the ultrafiltration pump 8 isactivated, a volume of the dialysate flowing out from the dialysateoutlet line L2 becomes greater than a volume of the dialysate flowing inthrough the dialysate inlet line L1 because the duplex pump P isquantitative. Accordingly, water is removed from the blood by thedifference between the volumes flowing out and flowing in. Devices otherthan the ultrafiltration pump 8 (e.g., a balancing chamber) may be usedto ultrafiltrate the blood. Further, the dialyzer 2, the duplex pump 3and the ultrafiltration pump 8 together form a dialyzing device in thehemodialysis treatment apparatus, which performs the hemodialysis andthe ultrafiltration by extracorporeally circulating the blood of thepatient.

The dialysis device 6 is electrically connected to a vital signdetecting device 9. The vital sign detecting device 9 is placed onto thepatient to detect vital signs, such as a blood pressure and a pulse, ofthe patient in a time-course of a hemodialysis treatment, and to outputvital sign values to the dialysis device 6. The vital signs refer tobio-information of the patient taking the hemodialysis treatment, andmay include, in addition to the blood pressure and the pulse, a breath,a body temperature, an oxygen saturation and a perspiration rate.

FIG. 3 is an exterior perspective view of the dialysis device 6 providedwith a display 13 that displays data of a current hemodialysis treatment(e.g., a duration of time passed and a ultrafiltration rate) on a screen13 a that is a touch panel screen. FIG. 4 is a block diagram of thedialysis device 6, showing an internal structure thereof. The display 13is electrically connected to a control device 12 that is connected to acirculating blood volume variation rate detecting device (herein “ΔBVdetecting device”) 10 and a hemodialysis condition detecting device 11.

The ΔBV detecting device 10 is electrically connected to the hematocritsensor 5 to calculate and detect a circulating blood volume variationrate ΔBV based on the hematocrit value sent from the hematocrit sensor5. In this regard, the ΔBV is obtained by the following formula wherethe Ht represents the hematocrit value obtained by the hematocrit sensor5.{(Ht at the start of the hemodialysis treatment−Ht at the time ofdetecting the ΔBV)/Ht at the time of detecting}×100

Accordingly, the ΔBV is detected as required during a time-course of thehemodialysis treatment.

The hemodialysis condition detecting device 11 detects, as required,hemodialysis conditions relating to hemodialysis and ultrafiltration ina time-course of the hemodialysis treatment (e.g., an ultrafiltrationrate and a venous blood pressure obtained by detecting an air-layer sideinternal pressure of the venous drip chamber 4 provided along the venousblood circuit 1 b). Values detected by the hemodialysis conditiondetecting device 11, the ΔBV detecting device 10 and the vital signdetecting device 9 are sent to the control device 12 to be processed anddisplayed at the display 13.

Specifically, the control device 12 controls the values detected by eachof the above-described detecting devices (i.e., the vital sign detectingdevice 9, the ΔBV detecting device 10 and the hemodialysis conditiondetecting device 11) so that the screen 13 a of the display 13 displaysthose values in graphs a, b, c and d aligned in parallel by time axes ofthe graphs as shown in FIG. 5. Each of the time axes is a horizontalaxis indicating elapsed time from the start of the hemodialysistreatment. Also, the screen 13 a displays additional data of the currenthemodialysis treatment, including a dialysate pressure, an accumulatedultrafiltration volume and a dialysate temperature. Displaying, in agraph or a chart, elapsed time from the start of the hemodialysistreatment and changes in detected values is hereinafter referred to a“time axis display.”

For example, the graph a is obtained by plotting, along the time axis,ΔBVs detected by the ΔBV detecting device 10. The graph b is obtained byplotting, along the time axis, venous blood pressures detected by thehemodialysis condition detecting device 11. The graphs c and d areobtained by plotting, along the time axis, blood pressures and pulses.Because the screen 13 a displays the graphs a, b, c and d at the sametime, aligning them in parallel by the time axes, changes in the valuesin the graphs are monitored and compared to each other visually andeffectively.

According to the embodiment of the present invention, the valuesdetected by the ΔBV detecting device 10 and by the vital sign detectingdevice 9 are together displayed on a single screen (i.e., the screen 13a) aligned by the time axes. Thus, when the ΔBV suddenly decreasesduring the hemodialysis treatment, the ΔBV is effectively compared tothe vital signs (e.g., the blood pressure and the pulse) to determinewhether the sudden decrease in the ΔBV is a sign indicating shocksymptoms of the patient.

In addition to the values detected by the ΔBV detecting device 10 and bythe vital sign detecting device 9, the values detected by thehemodialysis condition detecting device 11 (e.g., the venous bloodpressure in the above-described embodiment) are also displayed on thesame screen (i.e., the screen 13 a) in the graph b having the time axisaligned with the time axes of the graphs a, c and d indicating thevalues detected by the ΔBV detecting device 10 and the vital signdetecting device 9. Thus, when the ΔBV suddenly decreases during thehemodialysis treatment, the ΔBV is effectively compared to thehemodialysis conditions to determine whether the sudden decrease in theΔBV is due to changes in the hemodialysis conditions. In this regard, aslong as the graph a indicating ΔBV is on display, one or more of othergraphs indicating values of the vital signs and the hemodialysisconditions may be optionally displayed.

According to another embodiment of the present invention, a hemodialysistreatment apparatus, which also performs hemodialysis andultrafiltration by extracorporeally circulating blood of a patient, isprovided with a control device that controls a display on the display 13differently from the control device 12 in the above-describedembodiment. The control device in the another embodiment controls thedisplay 13 so that the values, which are detected by the detectingdevices including the vital sign detecting device 9, the ΔBV detectingdevice 10 and the hemodialysis condition detecting device 11, aredisplayed on a single screen in graphs on a single grid sharing a singletime axis.

For example, the graph a is obtained by plotting along the time axisΔBVs detected by the ΔBV detecting device 10. The graph e is obtained byplotting along the time axis ultrafiltration speeds detected by thehemodialysis condition detecting device 11. The graph c is obtained byplotting along the time axis blood pressures detected by the vital sighdetecting device 9. Because the screen 13 a displays the graphs a, c ande on the single screen on the single grid sharing the single time axis,changes in the values in the graphs are monitored and compared to eachother visually and effectively.

Further, according to this embodiment, because the values are comparedto each other visually on the single grid, a cause of the suddendecrease in the ΔBV are effectively identified. Also, a differentdisplay color may be used for each of the graphs so that the graphs arecompared to each other more visually.

According to this embodiment, the screen 13 a may display only graphsselected from available graphs. For example, when the graph a indicatingthe ΔBV and the graph c indicating the blood pressure are selected to bedisplayed, other graphs (e.g., the graph e indicating theultrafiltration speed) may be turned off from display. Accordingly,because selected graphs are efficiently displayed on the display 13 soas to be visually recognized better, changes in the values selected tobe displayed are compared to each other efficiently and effectivelythereby making a hemodialysis treatment analysis effective.

Further, according to this embodiment, the screen 13 a displays afunction key A indicated as “Event.” By touching the function key A, anexternal event that affects the hemodialysis treatment for the patient,and a time that external event occurs are input and displayed on thedisplay 13. Such external event includes a factor that may affect theΔBV, such as changes in body positions of the patient (e.g., changingfrom lying to sitting up on the bed), and taking medications or food.

For example, as shown in FIG. 6, when a medical staff inputs, bytouching the function key A, the changes in the body positions of thepatient, an arrow f is indicated along the time axis at the time thechanges occurred. Also, when the medical staff inputs, by touching thefunction key A, a factor that the patient takes a medication for aduration of time, an arrow g is indicated along the time axis at thetime and for the duration of the taking of the medication occurred. Thearrow g may be indicated by touching and retouching the function key Aat the time the patient starts and stops taking the medication,respectively. Alternatively, the arrow g may be indicated by touchingthe function key A at the time the patient starts taking the medicationand inputting the ending time of taking the medication. Further, sucharrow indicating the external event may be displayed with a numericalreference or icon, or replaced with another symbol, to inform themedical staff whether the arrow indicates the changes in the bodypositions of the patient or the taking of the medication.

Accordingly, because the time and the duration of the occurrence of theexternal event, which affects the hemodialysis treatment of the patient,are displayed on the screen 13 a, the values along the time axis areeffectively compared to the occurrence of such external event. Thus,when the sudden decrease in the ΔBV occurs, an analysis is efficientlyand effectively performed whether such sudden decrease is due to theexternal event. Moreover, the screen 13 a displays a function key Bindicated as “Complaint.” By touching the function key B, complaints bythe patient (e.g., nausea and headache) are input and displayed on thedisplay 13.

The present invention is not limited to the above-described embodiments.For example, the hemodialysis treatment apparatus may be provided with amemory that stores prior detected values detected by the ΔBV detectingdevice 10 in a prior hemodialysis treatment. Such prior detected valuesmay be plotted along the time axis in the grid indicating other valuesdetected by the ΔBV detecting device 10 and the vital sign detectingdevice 9 in the current hemodialysis treatment, so as to be displayed onthe display 13 together with the other values. In such an embodiment,changes in prior and current values of the ΔBV are efficiently andeffectively compared to each other to perform an effective hemodialysistreatment.

Specifically, it is preferable to obtain, based on the prior detectedvalues stored in the memory, an ideal range of changes in the ΔBV in thecurrent hemodialysis treatment, and display a maximum value Ma and aminimum value Mi of the ideal range in the same grid indicatingcurrently detected values of ΔBV. In this regard, the ideal range isdetermined by a medical staff, taking into consideration factorsincluding changes in prior detected values of the ΔBV, complaints by thepatient, an additional treatment applied, and results of hemodialysis(e.g., values relating to the ultrafiltration and blood tests).

Accordingly, because the ideal range of the changes in the ΔBV isobtained based on the prior detected values of ΔBV stored in the memory,and maximum values Ma and minimum values Mi of the ideal range aredisplayed in the same grid indicating the currently detected values ofthe ΔBV, it is effectively monitored in real-time whether the currentlydetected values of the ΔBV are within the ideal range, and effectivelycompared to the values detected by the vital sign detecting device 9.

Further, when the prior detected values are displayed, only predictedvalues or fair values of the ΔBV may be displayed on the screen 13 a.Also, the ideal range of the changes in the ΔBV may be displayed as aband graph having a width from the maximum to minimum values of theideal range. In addition, a regression curve may be obtained based onthe changes in the ΔBV detected in more than one prior hemodialysistreatment, and displayed on the same grid indicating the other valuesdescribed above.

Moreover, according to this embodiment, the ΔBV value is calculated anddetected, based on the hematocrit value Ht detected by the hematocritsensor 5. However, the ΔBV value may be calculated and detected based onother parameters. In addition, other than the blood pressure and thepulse of the patient as described above, the vital sign detecting device9 may detect other parameters as long as those parameters are vitalsigns of the patient.

Furthermore, according to this embodiment, the values detected by theabove-described devices are displayed in graphs on the screen 13 a.However, charts or tables having time axes aligned with each other maybe displayed on the screen 13 a. In addition, the length of the timeaxis or the lengths of the time axes may be standardized to show theduration of time in relation to the duration of a hemodialysistreatment, by setting a predetermined length or lengths for the timeaxis or axes, respectively, in relation to the width of the screen 13 aof the display 13. For example, if the duration of the hemodialysistreatment is longer than the predetermined length of the time axis, thenthe time axis for the duration is reduced. Similarly, if the duration ofthe hemodialysis treatment is shorter than the predetermined length ofthe time axis, then the time axis for the duration is extended. Also,although the screen 13 a of the display 13 is a touch panel screen, thedisplay 13 may be provided with a screen other than the touch panelscreen (e.g., a non touch panel LCD screen).

Obviously, numerous modifications and variations of the presentinvention are possible in light of the above teachings. It is thereforeto be understood that within the scope of the appended claims, theinvention may be practiced otherwise than as specifically describedherein.

1. A hemodialysis treatment apparatus comprising: a circulating bloodvolume variation rate detecting device configured to detect acirculating blood volume variation rate of a patient in a time-course ofa hemodialysis treatment; a vital sign detecting device configured todetect a vital sign value of the patient in the time-course of thehemodialysis treatment; and a display provided with a screen andconfigured to display both the circulating blood volume variation rateand the vital sign value on the screen along at least one time scale,the hemodialysis treatment apparatus dialyzing and ultrafiltratingextracorporeally circulating blood of the patient to perform thehemodialysis treatment.
 2. The hemodialysis treatment apparatusaccording to claim 1, further comprising: a hemodialysis conditiondetecting device configured to detect a hemodialysis condition value inthe time-course of the hemodialysis treatment, the hemodialysiscondition relating to hemodialysis and ultrafiltration in thehemodialysis treatment, wherein the screen displays the hemodialysiscondition value together with the circulating blood volume variationrate and the vital sign value, along the at least one time scale.
 3. Thehemodialysis treatment apparatus according to claim 1, wherein: the atleast one time scale is at least one time axis horizontally positionedin at least one grid; and the screen displays the circulating bloodvolume variation rate, the vital sign value and the hemodialysiscondition value in graphs, along the at least one time axis in the atleast one grid.
 4. The hemodialysis treatment apparatus according toclaim 3, wherein the screen displays at least two of the circulatingblood volume variation rate, the vital sign value and the hemodialysiscondition value in graphs, along a single time axis horizontallypositioned in a single grid.
 5. The hemodialysis treatment apparatusaccording to claim 4, wherein the screen displays all of the circulatingblood volume variation rate, the vital sign value and the hemodialysiscondition value in graphs, along a single time axis horizontallypositioned in a single grid.
 6. The hemodialysis treatment apparatusaccording to claim 1, wherein the screen displays an occurrence of anexternal event affecting the hemodialysis treatment for the patient sothat the occurrence is compared to the circulating blood volumevariation rate and the vital sign value displayed on the screen.
 7. Thehemodialysis treatment apparatus according to claim 1, furthercomprising: a memory configured to store a prior detected circulatingblood volume variation rate in a time-course of a prior hemodialysistreatment, wherein the screen displays, along the at least one timescale, the prior detected circulating blood volume variation ratetogether with the circulating blood volume variation rate and the vitalsign value detected in a time-course of a current hemodialysistreatment.
 8. The hemodialysis treatment apparatus according to claim 7,wherein: an ideal range of the circulating blood volume variation ratein the current hemodialysis treatment is obtained based on the priordetected circulating blood volume variation rate; and the screendisplays, along the at least one time scale, a maximum value and aminimum value of the ideal range together with the circulating bloodvolume variation rate and the vital sign value detected in thetime-course of the current hemodialysis treatment.
 9. A method forhemodialysis treatment, comprising the steps of: dialyzing andultrafiltrating extracorporeally circulating blood of a patient toperform a hemodialysis treatment; detecting a circulating blood volumevariation rate of the patient in a time-course of the hemodialysistreatment; detecting a vital sign value of the patient in thetime-course of the hemodialysis treatment; and displaying both thecirculating blood volume variation rate and the vital sign value on ascreen of a display along at least one time scale.